Is the 99 race Mopar hemi a Hemi motor or not?
426 Hemiroid motors were design, cast and put into production in late 1963 to help Dodge and Plymouth stay ahead of the other brands and the motors had to be installed on assembly line per NHRA and NASCAR rules at that time, hence the compromise on designing the valve train
As far as a billet all out aluminum race hemi that has had all the bad OEM design problems fix under todays rules that can't be ran on the street is it still consider Hemi or is it a all out custom built race motor
I think the first Hemi motor designs were made in air cooled aircraft engines in the early 1900s.
European car makers were using them long before Chrysler started making and installing them in the 1951 Chrysler V8 cars